You can comment on a blog entry simply by clicking on “Leave a comment” typing in your comment, putting an email and name and clicking on submit.
If you want to use a different name than your own, just get a free email account and use that. For some reason, WordPress does want an email address as well as a name.
If you would like to bring up a new topic (write an entry), please write it and submit via email to Sharon (email@example.com).
Sharon recommends drafting your comment in a word processing program, then copying into the form on the blog. This way if something blows up, you have the comment. Also, as time goes on, another discussion might call forth the same comment and you can just go back to an existing comment you saved without searching through the blog.